The invention relates to a semiconductor device, and more particularly to a flash lamp annealing device with a flash time control device.
After the ion-implantation of a wafer, the dopant damages the silicon crystal lattices on the surface of the wafer. To reconstruct the silicon crystal lattices, the wafer must be processed in an annealing procedure. One such annealing technique is known as furnace annealing, which processes the wafers in a batch type process but requires a longer processing period, such as 30 minutes or longer. Another annealing technique is known as Rapid Thermal Annealing, RTA, which reduces the amount of time that a semiconductor device is exposed to high temperatures during processing. Although the processing time required by the RTA is reduced to about 10 second or less, RTA is unsatisfied factor as it uses halogen lamps, which can form an extension with low resistance but the depth of the extension becomes large, such as, over 40-nm.
Flash lamp annealing is a new technology using a Xenon lamp to overcome annealing difficulties at the 65-nm manufacturing process technology node. The Xenon lamp of the flash lamp annealing device heats and maintains wafer temperature at over 900 degrees centigrade for only 0.8 milliseconds, about 1/3000 compared to about 2 seconds required by the present RTA processes. The present limitations of flash lamp annealing comprise process and hardware instability and the narrow process window for engineers to develop advanced processes. Moreover, the flash time is inflexible and the probability of wafer breakage is increased due to acute wafer variation temperature. A flash lamp annealing device with a flash time control device for widening the process window is desirable.